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# Technical FAQ with Lennard Zinn: Finding the right position

That sweet position on your road bike should be as comfortable as your favorite pair of slippers — and once you find it, you won’t want to give it up. But discovering the perfect position in the first place often requires many tiny adjustments in the height and reach of your handlebar to get it right.

In the current issue of VeloNews, technical writer Lennard Zinn helps you work through the steps necessary to find that perfect position. As mentioned in the article, Alan Hills of Hills-Scientific.com in Boulder, Colorado, has shared a handy program he designed to choose the stems for his bikes. As we promised, we have included Hills’s executable calculator below.

(Editor’s Note, October 2010: The calculator page referred to in this 2003 articles appears to be lost, the victim of our site’s two platform changes since then.)

This executable function is to make it possible for you to predict the reach and rise of the top of your handlebar from the steering tube at the top of your headset with stems of different lengths, angles, and clamp heights.

Note the following, especially noting the method for determining stem angle (and whether it is positive or negative):

Reach is the horizontal distance from center of steerer (at the center of the stem steerer clamp) to bar center.Rise is the vertical height from base of stem steerer clamp (headset top if no spacers under stem) to bar center.Angles are in degrees.Head tube angles are positive.Stem angles are relative to 90 degrees from the steering tube (i.e., a 90-degree stem would have a stem angle of zero).Stem angles are positive if greater than a right angle and negative if less than a right angle.All lengths are in millimeters.If you are using spacers under the stem, add their total thickness to the Rise

Calculating stem length and angle for your bike
To use this executable Web calculator yourself, you first have to figure out where you want your bar to be. You will need to know the head angle of your bike and the angle of your existing stem.

If you already know about where you want it, this may be as simple as acting on the feeling that you want to have your hands, say, 2cm (20mm) further out and a centimeter (10mm) higher than on your current setup. Then you can plug in the specs of your current stem into the formula to see what vertical rise and horizontal reach from the center of the steering tube at the base of the stem clamp you have. You can then add 20mm to the reach and 10mm to the rise and compare those numbers to the rise and reach obtained by plugging different available stem options into the formula.